Electric switch



E. L. OPPERMAN 1 ELECTRIC SWITCH Filed June 26. 1925 2 Sheets-Sheet l 1 1,645,01 091. 11,1927. V E. L OPPERMAN 9 l ELECTRIC SWITCH Filed June A26. 1925 2 Sheets-Sheet 2 Patented Oct. `11, 1927.

' 4 UN IT EDfi'f- ST A TE S f PATENTfoFF1-cE. i

EMIL L. OPPERMAN,OF' ROCHESTER', NEW YORK, ASSIGNOR r]I.O PRECISE MAN'U'FAC TUBING- CORPORATION,. F ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

' ELECTRIC SWITCH.

Application led June 26, 1925.l Serial No.l 39,681.

My present invention .relates to electric switches and more particularly to aswitch which is adapted to automatically cutoff the current to an electricmachine when the .5 latter becomes overloadedY and ithas for its object to 4provide a simple and serviceable switch particularly adaptedfor use on such mechanisms as domestic washing machines which are usually'operated by mechanically unskilledl persons. The improvements are directed in part toward the provision of a simple arrangement whereby the automatic circuit breaker is prevented from operating while the motor is `being vstarted and there is anA unavoidable overloadv thereon. To these and other ends the invent-ion resides in certain improvements and combinations of parts all as will be `hereinafter more fully described, the novelffeatures being pointed out in the claims at the end of-the speciiication.

In the drawings:

Figure 1 is a front view of-a switch cas-- ing containing al switch constructed in accordance with and illustrating one embodiment of my invention;

Figure 2 is a side viewzthereof;

Figures 3 and 4'are Vviews similar to Figur'e 1 but withithe'casing in section to disclose the operating partsand-showing the latter in different positions.

AFigure 5 is an enlarged sectionvthrough the shortcircuiting device taken on theline 5-5 of Figure 4;

Figure is a view similar to :FiguresB and 4 but withathe lcasing shell'removed;

.Figure 7 lis a side view of the 'switch mechanism with'thelcasing in section andshowing the opposite-*side'from' that-'shown in Figure 2;

Figure 8 is an enlarged 'section on the line 8-8 of :Figure 4;

Figure9 isa `.similar fragmentary section taken on 4the :line `9--9 of Figure A6- and F igure` 10 is an :enlarged section-taken on the line 101O of' Figure 6.

i Similar: reference numeralsthroughout the several views indicate theisame parts.

`The rinvent-ion is disclosed inthe present instance, by'way of illustration, as embodied in `an automatic switch apparatus of a variety particularly suitable for controlling the circuit of'a relatively 4small motor, such as employed for Aoperating washing Vmachines and the like, comprising preferably, af base 10 in the form of a block of insulating material to which is fitted a protective casing 11, as shown-for enclosing its yforwardside: on which are` mounted the operating parts.

Referring Y. more'especially to Figures and 4, theswitchportionl proper includes a pair of'spaced and-insulated contactmeans or clips 13 preferably of resilienteconducting strips of metal secured to the baseand having their ends curved downwardlytoe ward the base and t-hencefupwardly- .again in the form of aloop as-shown'. The ends are preferably providedfwith contact plates. 14 of substantial thickness and :wearing qualities. lThese contacts are secured by means of the usual nut and'screw device indicated.y at 15, the outer strip or a conducting extension thereof,fbeing provided witha bindingapost 1 6 for connection with one terminal. ofthe circuit to be controlled.v A movable switch contact 17 is provided as hereafter described for connecting the cooperatingwcontacts 14 and thereby closing the circuit.

Referring now more .particularly to the automatic means for openingfthe switch when the circuit exceeds a predetermined safe limit, the inner switch contact 14fhas its'secun ing screw` connect-ed by means of a wire 18 thro-ugh aslot 19, 'Figure 10, in the back of the base with oneterminal ofthe lcoil ofa sclenoid20 having a -U-shaped laminated core piece 21 extended exteriorlyflongitudinally of the coil as shown at 22.2 Theot-her terminal 23 offthecoil is connected with .a clip 24'on` thel base'hfaving'an outwardly 90 and downwardlyv looped light vspringwcontact member 25 (Figures 3 and 9) "secured thereto.I The opposite end of lthe-clip is provided with a binding post 26 foriconnection `with the other side of the controlledcir cuit. It isfthus apparentithatwhen the cont-acts 14 are connected by the'movable'switch part 17, the circuit extends from theouter to'the inner' of these contacts 14, thence through solenoid 20 to clip 24 and back tothe 100 line so that the'solenoid isincluded in .the controlled circuit. `Associated with the solenoid and actuated thereby is a mechanism for automatically effecting` movement of switch part 17 to open the circuit when the'105 1current becomes excessive as described 'be- The movable switch part 17 is preferably in the form of a shoe', Figures .4 and 5, pivotall-vl and thusyieldably supported as at 110 27 on a clip 28 carried by and insulated from a switch lever 29 pivoted at 30 on a post 31 carried by the base. rlhe shoe or contact 17 is thus adapted to yieldably accommodate itself to engagement with both contacts 14 in the vclosed position ofthe switch, (Figure 4). Lever 29 is formed with a recess or notch 32 in its lower edge, Figure 8, for engagement with the recessed portion 33 of a push button 34 guided and sliding longitudinally in a bearing 35 on the base. Manual depression of this button therefore, serves to swing lever 29 on its pivot to engage the contact means and close the switch against the action of a spring 36 having one end adjustably connected as at 37a with the `opposite arm of the lever 29 as more particularly described hereafter.

i Means are provided for retaining the switch in closed position until opened under the action of spring 36 either by the overload solenoid 20 already described or by manual means explained hereafter. Such means comprises an angular portion 37 on the other end of switch lever 29 which portion has an extended lug 38 struck laterally to'provide at 39 a seat for engagement with the Yend 40 of a latching lever 41 pivotally supported at 42 on the` extension 22 of the solenoid core. The other end 43 of the latching lever is positioned and adapted to function as an armature for actuation by solenoid 2O which pulls this end of the lever in a direction to move its opposite end 40 out of latching engagement with the switch lever. Spring 36 has its outer end connected as at 44 with the latching lever so that this single spring serves economically and compactly to not only move the switch lever to open position but also the latching lever into engagement with the switch lever in opposition to the force of the solenoid. Manual means are also provided for swinging the latching lever to release the switch lever for movement by the *spring comprising a push button 45 extending through an opening in the casing into attachment with a leaf spring 46 vfixed on the casing7 the parts being so positioned that the depression of the button carries its inner end into engagement with the latching lever and trips the latter to open the switch.

Attached to the clip portion 29 of the switch lever and hence in electrical contact with it and the shoe 17 is a light spring arm 28. `When the switch is open and the device is in the normal position of Figures 3 and 9, the spring contact member 25 is expanded and tends to push the button 34 outwardly by engagement with the end thereof. The spring arm 28a extends through the loop of the contact member but in this normal position is outof contact with it as clearly shown in Figure 9. hen the button 34 is pressed in to move the switch arm to closed position it first moves contact 25 to the depressed position of Figure 8 in which it picks up spring arm 28d and makes electrical contact therewith. This serves to short circuit the solenoid during such engagement and release the latching lever 44. Upon further inward movement of the button a shoulder 342L thereon picks up the switch lever 29 and'in'o'ves the switch element i7 into engagement with the yielding contacts 13 and 14 so vthat the circuit is closed with the solenoid shorted out. This permits the motor to assume the overload necessary in starting without being cut off.

In the meantime the switch lever is positioned for latching by the latching lever as the deenergizing of the solenoid releases the latching lever for movement by its spring to latching position. Upon releasing the button 34 it is thrust outwardly by the spring contact member 25 as ,shown in Figure 9 and contact with the spring arm 23 is broken as shown in Figures G and 9 so that the coil is again connected in circuit. The button has the lost motion connection with the switch lever as shown to permit this release of the contact member 25 while the switch is still closed. To summarize the operation, with the device connected in the circuit to be controlled7 depression of finger piece or button 34 ,first short circuits the solenoid and then closes the switch and moves the switch lever into latching engagement with the latching lever. rEhe shorting contact is maintained in this way sufficiently long for the motor to get under way before the latchingP lever can he influenced to immediately release the switch. Should the current in the circuit exceed a predetermined value, its energizing effect upon the solenoid causes the latter toiattract the corresponding end of the latching lever, the opposite end of which releases the switch lever which is quickly moved by spring 36 to open the circuit. Or if this safety feature does not come into operation, button 45 is depressed when it is desired to' break the circuit and the latching lever is thus manually actuated to release the switch lever for movement to opened position.

I claim as my invention:

l. In an apparatus of the class described, the combination of a circuit controlling switch automatically occupying a given one of a plurality of positions to which the switch is movable, retaining means for holding the switch against said automatic movement, a device included in circuit with the switch for automatically actuating said retaining means to release the switch, an clement arranged for inclusion in the circuitand having connections for short circuiting said device, and means for progressively operating` the short circuiting elementand then the switch.

2. In an apparatus of the class described, the combination of a circuit controlling switch automatically occupying a given one of a plurality oi' positions to which. the switch is movable, a pivoted latching lever for holding the switch against said automatic movement, solenoid means included in circuit with the switch for automatically actuating said lever to release the switch, and contact means closed prior to a closing movement of the switch and having connections for short circuitingsaid solenoid means.

3. In an apparatus of the class described, the combination of a circuit controlling switch automatically occupying a given one of a. plurality of positions to which the switch is movable, a pivoted latching lever for holding the switch closed against said automatic movement, solenoid means included in circuit with the switch for automatically actuating said lever to release the switch, a pair of contacts disengaged in each of said switch positions and engaged temporarily prior to the movement of the switch to closed position, and connections for short circuiting said solenoid means by the engagement of said contacts.

4. In an apparatus of the class described, the combination of a circuit; controlling switch manually movable to closed position, manually operable latch means for holding said switch in closed position, solenoid means tor moving said latch means to switch releasing position, spring means for moving said switch to open position and said latch means to switch retaining position, contact means for shortcircuiting said solenoid means and a manually operable member for actuating said short circuiting means and thereafter closing the switch.

the combination of a circuit controlling switch manually movable to closed position, manually operable latch means for holding said switch in closed position, solenoid means for moving said latch means to switch releasing position, spring means for moving said switch to open position and said latch means to switch retaining position, contact means tor short circuiting said solenoid means embodying a spring contact member and a con nection from the switch member arranged in the path of said contact member, and operating means adapted to lirst bring the spring contact member and the switch mem ber connection into contact to complete the short circuit and to thereafter close the switch.

6. In an apparatus of the class described, the combination of a circuit controlling switch manually movable to closed position, manually operable latch means for holding said switch in closed position, solenoid means tor moving said latch means to switch releasing position, spring means for moving said switch to openposition and said latch means to switch retaining position, cont-act means for short circuiting said solenoid means embodying a spring contact member and a connection from the switch member arranged in the path ot said contact member, and operating means adapted to first bring the spring contact member and the switch member connection into contact to complete the short circuit and to thereafter close the switch, said operating means embodying a movable device having a lost motion connection with the switch.

EMIL L. OPPERMAN. 

